• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.41 no.2
• /
• pp.101-111
• /
• 2021

Two different types of shear-friction tests were classified by external loadings and referred to as a push-off and a pull-off test. In a pull-off test, a tension force is applied in the transverse direction of the test specimen to produce a shear stress at the shear plane. This paper presents a method to evaluate shear transfer strengths of uncracked pull-off specimens. The method is based on the compression field theory and different constitutive laws are applied in some ways to gain accurate shear strengths considering softening effects of concrete struts based on Modified Compression Field Theory (MCFT) and Softened Truss Model (STM). The validity of the proposed method is examined by applying to some selected test specimens in literatures and results are compared with the predicted values. A general agreement is observed between predicted and measured values at ultimate loading stages in initially uncracked pull-off test specimens. A shear strength evaluation formula considering the effective compressive strength of a concrete strut was proposed, and the applicability of the proposed formula was verified by comparing with the experimental results in the literature.

• Journal of Information Technology Services
• /
• v.16 no.1
• /
• pp.99-118
• /
• 2017

Growing importance of online security on certification, many of the web-related security technology introduced day by day. Especially, using smart certificate (USIM) is recognized as one of the most safe and convenient method for the security of public certificate. The purpose of this study is to find the factors that affect the Intention of switching to smart certificate for the general public who use public certificate service. Based on migration theory, this study determined the relationship between pull factors, push factors and mooring factors which can affect the intention of switching to smart certificate. To empirically analyze the proposed hypothesis, the statistical analysis were conducted based on the response from 350 public certificate service users using SPSS 22.0 and Smart PLS 2.0. The results of this study can be summarized as follows. First, system quality, one of the pull factors has positive influence on perceived ease of use. On the other hand, the other pull factor, service quality has positive influence on both perceived ease of use and perceived usefulness. Second, push factors, user experience and information security awareness have positive influence on perceived ease of use only. Third, mooring factor, switching cost does not have influence on switching intention while perceived usefulness has positive influence on. The results of this research can be used for whom has interest to the switching intention of public certificate service for online security and provide the proper understanding about smart certificate service mechanism.

• The Journal of Information Systems
• /
• v.30 no.4
• /
• pp.43-69
• /
• 2021

Purpose Although companies occupied the network market take the advantageous position first and can be successful in securing users over a certain size, it is important to satisfy the customers' demand and prevent the outflow of users toward a new alternative SNS. What is more, there are frequent changes in the flow of users toward new SNSs. Despite these dynamic market circumstances, there is a lack of research to explain the switching behaviors of SNS users. Design/methodology/approach The objective of this study is to explain and verify a specified migration theory(Push-Pull-Mooring model) focused on SNS fatigue in the psychological point of view, as well as reviewing previous studies on functional and technical characteristics of SNSs themselves. Moreover, this study tried to highlight factors affecting users actual SNS switch rather than their switching intention. Findings According to the statistical analysis, the most influenced pull factor to switch SNS was the alternative attractiveness. On the other hand, undesired relationship burden, service innovation and important mooring factors to prevent users' SNS switch. This study has a significant contribution to the theory, which analyzed users' actual SNS switch, and examined SNS users' psychological factors(SNS fatigue), reviewing the characteristics of existing services. To secure more users and to keep them, companies providing social network service need to develop differentiated strategies by analyzing psychological characteristics of various users.

• Korean Management Science Review
• /
• v.30 no.2
• /
• pp.63-77
• /
• 2013

Recently, many companies are interested in adopting cloud computing as their IT strategy. However, no distinct results have appeared in the substantial implementation of this technology. The main reason for such result is from the absence of research models leading to high impact studies on cloud computing. Thus, this study attempts to find a possible answer for the following research question : what factors influence an organizational assimilation of cloud computing? This study investigates Technology-Push (TP)/Need-Pull (NP) theory as a main factor affecting cloud computing assimilation. Also, the study examines the moderating role of organizational readiness. TP includes of perceived benefits, vendor pressure, cost savings, and IT activity intensity while NP includes competitor orientation, information technology policy, technological turbulence, and performance gaps. In addition, organizational readiness suggests two variables, financial resources and technological knowledge. Result from 217 adopting organizations showed that all of these factors with exception of competitor orientation and vendor pressure, have statistically significant impact on assimilation of cloud computing. The implications of the findings propose a theoretical framework for the foundation of studies on cloud computing assimilation, which can server as important practical guidelines for technology development.

• Journal of the Korean earth science society
• /
• v.37 no.1
• /
• pp.62-77
• /
• 2016

In the early model of plate tectonics, the plate was depicted as a passive raft floating on the convecting mantle and carried away by the mantle flow. At the same time, ridge push at spreading boundaries and drag force exerted by the mantle on the base of lithosphere were described as the dominant driving forces of plate movements. However, in recent studies of plate tectonics, it is generally accepted that the primary force driving plate motion is slab pull beneath subduction zones rather than other forces driven by mantle convection. The current view asserts that the density contrast between dense oceanic lithosphere and underlying asthenosphere is the substance of slab pull. The greater density of oceanic slab allows it to sink deeper into mantle at trenches by gravitational pull, which provides a dominant driving force for plate motion. Based on this plate tectonics development, this study investigated the contents of plate tectonics in high school Earth Science textbooks and how they have been depicted for the last few decades. Results showed that the early explanation of plate movement driven by mantle convection has been consistently highlighted in almost all high school textbooks since the 5th curriculum, whereas most introductory college textbooks rectified the early theory of plate movement and introduced a newly accepted theory in revised edition. Therefore, we suggest that the latest theory of plate tectonics be included in high school textbooks so that students get updated with recent understanding of it in a timely manner.

• Journal of Intelligence and Information Systems
• /
• v.22 no.1
• /
• pp.19-41
• /
• 2016

Recently, the proliferation of mobile devices such as smartphones and tablet personal computers and the development of information communication technologies (ICT) have led to a big trend of a shift from single-channel shopping to multi-channel shopping. With the emergence of a "smart" group of consumers who want to shop in more reasonable and convenient ways, the boundaries apparently dividing online and offline shopping have collapsed and blurred more than ever before. Thus, there is now fierce competition between online and offline channels. Ever since the emergence of online shopping, a major type of multi-channel shopping has been "showrooming," where consumers visit offline stores to examine products before buying them online. However, because of the growing use of smart devices and the counterattack of offline retailers represented by omni-channel marketing strategies, one of the latest huge trends of shopping is "webrooming," where consumers visit online stores to examine products before buying them offline. This has become a threat to online retailers. In this situation, although it is very important to examine the influencing factors for switching from online shopping to webrooming, most prior studies have mainly focused on a single- or multi-channel shopping pattern. Therefore, this study thoroughly investigated the influencing factors on customers switching from online shopping to webrooming in terms of both the "search" and "purchase" processes through the application of a push-pull-mooring (PPM) framework. In order to test the research model, 280 individual samples were gathered from undergraduate and graduate students who had actual experience with webrooming. The results of the structural equation model (SEM) test revealed that the "pull" effect is strongest on the webrooming intention rather than the "push" or "mooring" effects. This proves a significant relationship between "attractiveness of webrooming" and "webrooming intention." In addition, the results showed that both the "perceived risk of online search" and "perceived risk of online purchase" significantly affect "distrust of online shopping." Similarly, both "perceived benefit of multi-channel search" and "perceived benefit of offline purchase" were found to have significant effects on "attractiveness of webrooming" were also found. Furthermore, the results indicated that "online purchase habit" is the only influencing factor that leads to "online shopping lock-in." The theoretical implications of the study are as follows. First, by examining the multi-channel shopping phenomenon from the perspective of "shopping switching" from online shopping to webrooming, this study complements the limits of the "channel switching" perspective, represented by multi-channel freeriding studies that merely focused on customers' channel switching behaviors from one to another. While extant studies with a channel switching perspective have focused on only one type of multi-channel shopping, where consumers just move from one particular channel to different channels, a study with a shopping switching perspective has the advantage of comprehensively investigating how consumers choose and navigate among diverse types of single- or multi-channel shopping alternatives. In this study, only limited shopping switching behavior from online shopping to webrooming was examined; however, the results should explain various phenomena in a more comprehensive manner from the perspective of shopping switching. Second, this study extends the scope of application of the push-pull-mooring framework, which is quite commonly used in marketing research to explain consumers' product switching behaviors. Through the application of this framework, it is hoped that more diverse shopping switching behaviors can be examined in future research. This study can serve a stepping stone for future studies. One of the most important practical implications of the study is that it may help single- and multi-channel retailers develop more specific customer strategies by revealing the influencing factors of webrooming intention from online shopping. For example, online single-channel retailers can ease the distrust of online shopping to prevent consumers from churning by reducing the perceived risk in terms of online search and purchase. On the other hand, offline retailers can develop specific strategies to increase the attractiveness of webrooming by letting customers perceive the benefits of multi-channel search or offline purchase. Although this study focused only on customers switching from online shopping to webrooming, the results can be expanded to various types of shopping switching behaviors embedded in single- and multi-channel shopping environments, such as showrooming and mobile shopping.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.23 no.59
• /
• pp.21-36
• /
• 2000

The drum-buffer-rope(DBR) system is a finite scheduling mechanism that balances the flow of the production system. DBR controls the flow of materials through the plant in order to produce products in accordance with market demand, with a minimum of manufacturing lead time, inventory, and operating expenses. This paper integrates the best of MRP push system and JIT pull system with DBR system, efficiently adapts these logics to capacity constraint resources, and contributes to the evolution of synchronous manufacturing. The purpose of this paper is, thus, threefold. The first objective is to identify the frame of theory of constraints(TOC) and the logic of DBR scheduling. The second objective is to formulate the DBR constraint scheduling problems(DBRCSP) in a job shop environments. Finally, the paper is to suggest the solution procedure of DBRCSP for embedding TOC into MRP/JIT along with an numerical expression. In addition, illustrative numerical example is given.

• Journal of Power Electronics
• /
• v.9 no.1
• /
• pp.61-67
• /
• 2009

In this paper, a simple technique is presented for robust stability testing of perturbed DC-DC converters having multi-linear uncertainty structure. This technique provides a necessary and sufficient condition for testing robust stability. It is based on the corollary of Routh criterion and gridding of parameters. The previous work based on parametric control theory using Kharitonov's theorem and Hermite Biehler theorem gives conservative results and only the sufficient condition of stability, whereas the proposed method provides the necessary and sufficient condition for testing robust stability and it is computationally efficient. The superiority of the method is compared with the Edge theorem.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.6
• /
• pp.1996-2011
• /
• 2021

To understand a trend is to explore the intricate process of how something or a particular situation is constantly changing or developing in a certain direction. This exploration is about observing and describing an unknown field of knowledge, not testing theories or models with a preconceived hypothesis. The purpose is to gain knowledge we did not expect and to recognize the associations among the elements that were suspected or not. This generally requires examining a massive amount of data to find information that could be transformed into meaningful knowledge. That is, looking through the lens of big-data analytics with an inductive reasoning approach will help expand our understanding of the complex nature of a trend. The current study explored the trend of well-being in South Korea using big-data analytic techniques to discover hidden search patterns, associative rules, and keyword signals. Thereafter, a theory was developed based on inductive reasoning - namely the hook, upward push, and downward pull to elucidate a holistic picture of how big-data implications alongside social phenomena may have influenced the well-being trend.

• CELLMED
• /
• v.8 no.4
• /
• pp.25.1-25.2
• /
• 2018

The aim of this article is to suggest that Samulnori will be able to produce better and more lovable language. Samulnori is a good example of the Korean music. Samulnori is originally meaning four-percussion play. Janggu and buk made of leather which were mainly cowskin and dogskin. But jing and kkaengwari made out of brass. Four percussions are an instrument composed of a pattern based on the theory of yin and yang. The principle of Samulnori rhythms are well made up of the relaxation, tension, improvisation, escalating rhythms, and dynamic sound. Samulnori looks like two lovers exchanging sweet words in the natural forest. The push and pull between four instruments like a love quarrel. The author feels that the rhythms of the four instruments are like the whispers and cries of lovers. In conclusion, the silent or passionate rhythm of Samulnori feels like two lovers' tightrope love. The author thinks it creates a rich language of love.